Re: [PATCH v7 5/8] CPPC: Add a CPUFreq driver for use with CPPC

[Sudeep Holla <sudeep.holla@arm.com>]

On 09/07/15 19:04, Ashwin Chaugule wrote:
> This driver utilizes the methods introduced in the previous
> patch - "ACPI: Introduce CPU performance controls using CPPC"
> and enables usage with existing CPUFreq governors.
>
> Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
> Reviewed-by: Al Stone <al.stone@linaro.org>
> ---
>   drivers/cpufreq/Kconfig.arm    |  16 ++++
>   drivers/cpufreq/Makefile       |   2 +
>   drivers/cpufreq/cppc_cpufreq.c | 197 +++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 215 insertions(+)
>   create mode 100644 drivers/cpufreq/cppc_cpufreq.c
>
> diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
> index 4f3dbc8..578384d 100644
> --- a/drivers/cpufreq/Kconfig.arm
> +++ b/drivers/cpufreq/Kconfig.arm
> @@ -272,3 +272,19 @@ config ARM_PXA2xx_CPUFREQ
>   	  This add the CPUFreq driver support for Intel PXA2xx SOCs.
>
>   	  If in doubt, say N.
> +
> +config ACPI_CPPC_CPUFREQ
> +	tristate "CPUFreq driver based on the ACPI CPPC spec"
> +	depends on ACPI_CPPC_LIB
> +	default n
> +	help
> +	  This adds a CPUFreq driver which uses CPPC methods
> +	  as described in the ACPIv5.1 spec. CPPC stands for
> +	  Collaborative Processor Performance Controls. It
> +	  is based on an abstract continuous scale of CPU
> +	  performance values which allows the remote power
> +	  processor to flexibly optimize for power and
> +	  performance. CPPC relies on power management firmware
> +	  for its operation.

Why is this ARM specific ? It might be used only on ARM but doesn't mean
it should be visible only on ARM ACPI systems.

Regards,
Sudeep